Move protocol_version to core.release

IPython/core/release.py

@@ -38,6 +38,9 b" __version__ = '.'.join(map(str, _ver))"
 version = __version__  # backwards compatibility name
 version_info = (_version_major, _version_minor, _version_micro, _version_extra)
 
+# Change this when incrementing the kernel protocol version
+kernel_protocol_version_info = (4, 0)
+
 description = "IPython: Productive Interactive Computing"
 
 long_description = \

IPython/zmq/ipkernel.py

@@ -35,11 +35,11 b' from zmq.eventloop import ioloop'
 from zmq.eventloop.zmqstream import ZMQStream
 
 # Local imports
-import IPython
 from IPython.config.configurable import Configurable
 from IPython.config.application import boolean_flag, catch_config_error
 from IPython.core.application import ProfileDir
 from IPython.core.error import StdinNotImplementedError
+from IPython.core import release
 from IPython.core.shellapp import (
     InteractiveShellApp, shell_flags, shell_aliases
 )
@@ -54,7 +54,7 b' from IPython.utils.traitlets import ('
 from entry_point import base_launch_kernel
 from kernelapp import KernelApp, kernel_flags, kernel_aliases
 from serialize import serialize_object, unpack_apply_message
-from session import Session, Message, protocol_version
+from session import Session, Message
 from zmqshell import ZMQInteractiveShell
 
 
@@ -62,7 +62,8 b' from zmqshell import ZMQInteractiveShell'
 # Main kernel class
 #-----------------------------------------------------------------------------
 
-ipython_version = list(IPython.version_info)
+protocol_version = list(release.kernel_protocol_version_info)
+ipython_version = list(release.version_info)
 language_version = list(sys.version_info[:3])
 
 

IPython/zmq/session.py

@@ -74,9 +74,6 b' def squash_unicode(obj):'
 # globals and defaults
 #-----------------------------------------------------------------------------
 
-# Change this when incrementing the kernel protocol version
-protocol_version = [4, 0]
-
 # ISO8601-ify datetime objects
 json_packer = lambda obj: jsonapi.dumps(obj, default=date_default)
 json_unpacker = lambda s: extract_dates(jsonapi.loads(s))